Carton closing machine



N ov. 28, 1961 M. J. LAWRENCE 3,010,266

CARTON CLOSING MACHINE Filed Nov. 4, 1958 5 Sheets-Sheet l fifili. `r

Nov. 28, 1961 M. J. LAWRENCE CARTON CLOSING MACHINE 5 sheets-'sheet 2 Filed Nov. 4, 1958 Nov. 28, 1961 M. J. LAWRENCE CARTON CLOSING MACHINE 5 Sheets-Sheet 5 Filed Nov. 4, 1958 Nov. Z8, 1961 M. .1. LAWRENCE 3,010,255

CARTON CLOSING MACHINE Filed No'v. 4, 195s 5 sheets-sheet 4 Nov. 28, 1961 M. J. LAWRENCE 3,010,266

CARTON CLOSING MACHINE Filed Nov. 4, 1958 5 Sheets-Sheet 5 United States Patent 3,010,266 CARTON CLOSING MACFIINE i Michael J. Lawrence, Chicago, Ill., assxgnor to Chlcago Carton Company, a corporation of Delaware Filed Nov. 4,1958, Ser. No. 771,914 Claims. (Cl. 53-376) The present invention relates generally to the closure of cartons, and more particularly to a method for closing paperboard cartons and to a machine for carrying out the carton closure method.

Accordingly, the principal object of the present mvention is the provision of a new `and improved method for closing cartons and for the provision of an apparatus which is suited to employ said closure method and which includes features aifording use of the apparatus with cartons of various dimensions and closure arrangements.

A still further object of the present invention is to provide a compact machine of the character indicated that is relatively simple in operation and fabricatlon, which is highly reliable in performance and which will operate satisfactorily over long periods of time without breakdown or need of repair.

Other objects and advantages of the present invention will be understood by the reference to the following description and the accompanying drawings wherein the carton closure method of this invention is described and illustrated and wherein one embodiment of a carton closing apparatus constructed in accordance with-this invention is also described and illustrated.

In the drawings:

FIGURE l is a side elevational view of one selected form of a carton closing machine embodying various of the features of the present invention;

FIGURE 2 is a top view of lthe apparatus shown in FIGURE 1; Y n

FIGURE 3 is an end view looking from the right of FIGURE '1;

FIGURE 4 is a diagrammatic view illustrating various positions of the carton during travel through the apparatus shown in the preceding views;

FIGURE 5 is an enlarged sectional view taken along line 5-5 of FIGURE 4;

FIGURE 6 is an enlarged sectional line 6 6 of FIGURE 4;

FIGURE 7 is `an enlarged elevational view taken along line 7 7 of FIGURE 4;

FIGURE 8 is an enlarged view taken along line 8-8 of FIGURE 4;

FIGURE 9 is an enlarged view taken along line 9--9 of FIGURE 4;

FIGURE 10 is Aan enlarged view taken along line 10-10 of FIGURE 4;

FIGURE l1 is an 11-11 of FIGURE 4;

FIGURE 12 is an 12--112 of FIGURE 4;

FIGURE 13 is an 13 13 of FIGURE 4;v

FIGURE 14 is an enlarged fragmentary view taken along line 14-1'4 of FIGURE 2;

FIGURE 15 is av sectional view taken along line 15--15 of FIGURE 14;

FIGURE 16 is an enlarged elevational view taken along line l16-16 of FIGURE 2;

FIGURE 17 is a sectional view taken along line 17-17 of FIGURE 16;

FIGURE(v 1-8 is a sectional view taken along line 18-#18 of FIGURE 16;

FIGURE 19 is an enlarged fragmentary view with view taken along enlarged view taken along line enlarged view taken along line enlarged view taken along line ICC 2 V parts broken away, taken along line 19--19 of FIG- URE 2;

FIGURE 2O is an enlarged perspective view of the carton prior to the closing operation; and

FIGURE 2l is a perspective view of the carton with parts broken away after the closing operation.

Seen generally in FIGURES l and 2. is one embodiment of a carton closing machine which embodies various of the features of the present invention and which is adapted to be associated in series with other equipment in an automatic food pack-aging assembly line.

The machine described herein is particularly adaptedrto close a carton such as shown in FIGURE 20 and indicated throughout the drawings =by the reference numeral 25. It will be readily apparent, however, that the disclosed machine is not limited in operation to the particular carton shown in FIGUR-E 20, but may be advantageously employed with -a wide range of rectangular cartons having varying dimensions and varying cover flap and cover tuck arrangements. A

The particular carton 25 illust-rated in FIGURE 20 iS fabricated of paperboard and is of substantially rect-anguF lar form, having a bottom wall 27, a yfront -wall 29 and a rear wall 3'1 which are foldably connected to the bot-` tom wall, and which define the width of the carton, and a pair of opposed side walls 33 and 35, which are also foldably connected to the bottom wall, and which define the length of the carton. For convenience in the description of the various machine operations, the opposed side walls 33 and 35 will be respectively referred to as the leading and trailing side walls.

Foldably connected along a hinge line 37 to the rear wall 31 is a generally rectangular cover panel 39 having a cover tuck 41 extending therefrom along a fold line 43. In addition, front, leading and trailing cover aps 45, 47 and 49 extend foldably along respective hinge lines 51, 53 and 55 yfrom the front and side walls 29, 33 and 35. The front cover ap 45 includes a slit 57 which is formed with its ends terminating along the fold line 51 and which provides for the formation of a slot 59 incident to the infolding of the front cover flap 45 as shown in FIGURE 2l. The slot 59 receives the cover tuck 41 to secure the cover flaps and cover panel in proper closed relation to the remainder of the carton, also as shown in FIGURE 2l.

The disclosed apparatus, as shown in FIGURES l and 2 includes generally a supply conveyor 61 -for receiving unclosed cartons in random sequence from a previous operation, a main conveyor 63 l'for transporting the cartons to be closed passed a series of units whichsequentially affect the closure of the cartons, and a mechanism 65 for transferring the open cartons from the supply conveyor to the main conveyor at predetermined intervals correlated to the travel of the main conveyor and to the action of the various operating units. In addition, a suitable drive mechanism 67 is incorporated in the disclosed machine to power and coordinate the various operating components. For purposes of convenience in description, the end of the carton closing machine, seen to the right in FIGURE l, will be referred toas the forward end, and reference will be made to the right and left sides of the machine looking from the foreward end thereof,- as seen in FIGURE 3.

In order to clarify the following disclosure and to orient the sequential operations performed by the various machine components, a brief summary of th`e machine operation will first be described.

The open cartons are delivered to the supply conveyor 6i (see FIGURE l) in random sequence from a prior filling or loading operation With the leading side wall 33 of the carton positioned rearwardly and in generally transverse relation to the travel of the supply conveyor for movement therealong until intercepted by the transfer mechanism 65 which locates the individual cartons in the path of travel of the main conveyor 63 for transportation past the various closure units. In this connection, the front cover flap 4'5 is first folded outwardly of the carton -by operation of a front flap folding unit 69 which includes an oscillating blade 71 (FIGS. 5 and 6). Aslthe carton travels on it passes under a bar assembly 77 forming a part of a longitudinally extending closure unit 79, and the leading cover ap 47 is folded inwardly of the carton (FIG. 7). Approximately simultaneously with the folding of the leading cover flap 47, the trailing cover flap 49 is folded inwardly of the carton by means of a trailing ap folding unit 73 which includes a plurality of rotating camming fingers 75. As the carton progresses farther along the path of travel of the main conveyor, the cover panel 39, which is still in generally upstanding condition, passes into a cover tuck folding unit 81 which effects folding of the cover tuck 41 relative to the cover panel 39. Continued travel of the carton along the conveyor path causes lfolding of the front cover flap 45 inwardly ofthe carton by means of a guide element 84 carried on the closure unit l79 (FIG. 9). Approximately simultaneously with the infoldng of the front cover ap 45, the cover panel 39 is intercepted by a rod assembly 83 cariied on the closure unit 79 to fold the cover panel 39 downwardlyover the carton (FIG. 10). Also supported on vthe closure unit 79 is a deilector 85 which guides the cover tuck'41 for insertion within the slot 59 formed by infolding of the front cover flap 45 to thereby secure the cover panel in closed relation to the carton (FIGS. 10 and' 1l). The carton then travels under a press roll unit 87 (FIG. 12) to complete the closing of the cover panel arid to lock the cover tuck to the front flap. Finally, the carton is deposited on a delivery platform 89 (FIG. 4) to complete the sequence of operations.

' Referring now, in greater detail to the construction of the disclosed apparatus, as seen in FIGURES 1, 2 and 3, the various components of the carton closing machine are Vcarried on a generally rectangular framework or standj91 which is provided with casters or Wheels 93 to permit the machine to be moved from one location to another as desired. Of course, a floor lock (not shown) is also included to prevent `accidental or inadvertent movement or dislocation of the apparatus when in operation with other associated equipment.

Supply conveyor The cartons to be closed are supplied to the closing apparatus from a previous filling or loading operation and deposited on the supply conveyor 61 which is spaced laterally Ifrom the foreward end of the main conveyor 63 in generally parallel relation thereto and which extends outwardly of the foreward end of the stand 91. As shown in FIGURES 1, 2 and 3, the supply conveyor 63 comprises an endless belt 95 disposed about a drive pulley 97 journalled within theV stand 91 and a pair of idler pulleys 99 and 101. The idler pulley 99 is adjustably journalled between a pair of triangularly shaped braces 103 which are secured to the forward end of the stand 91 intermediate the drive pulley 97 and idler pulley 99. In order to align the unclosed cartons for travel along the conveyor, a fence assembly 107 is situated to each side of the beit 95. Each of the Ifence assemblies 107 is -adjustably mounted to the adjacent brace 103 fby means permitting adjustment of the distance between the fence assemblies in order to accommodate various size cartons.

Main conveyor in parallel spaced relation. The upper flanges of the channel members 111 deiine a bed 113 for supporting the cartons as they are propelled by the main conveyor 63 past the various units during the closure operations. Also mounted on the main support 109 is a rail or guide assembly 115 comprising a plurality of L-shaped brackets 117 -which cooperate to carry a pair of rails 119 extending lengthwise of the conveyor to form a fence to the right of the conveyor path which assists in maintaining proper positioning of the cartons during travel along the conveyor path y(FIGS. 5, 6 and 7). The rails 119 are suitably secured to one of the legs of the -brackets 117, `and the other leg of the brackets is secured to the main support 109 through a slotted bolt connection affording lateral adjustment of the guide assembly 11'5 relative to the bed 113 to provide for the accommodation of cartons of various widths. Y f l The main conveyor 63 comprises an endless chain 121 which is disposed with the upper run located between the webs of the channel members 111 and which can-ies a plurality of pusher elements 123 on legs 133 in evenly spaced relation therealong. Of course, the spacing of the pusher elements along the chain is coordinated in predetermined relation to the speed of the chain and the movement of the operating components.V In addition, the main support is provided at each end of the conveyor run with a suitable aperture or opening to permit the endless chain and pusherelements to pass therethrough. The main conveyor 63 is trained about a drive sprocket 124 (see FIGURE 1) journalled forwardly in a bearing secured to the undersurface of the main support, a first idler sprocket 125 jonrnalled rearwardly in a bearing secured to the undersurface of the .main support 109, and a second idler sprocket 127 supported on a depending post 129 ixedly secured to the undersurface of the main support 109.

The pusher elements 123 may take a variety of forms, however, in this selected embodiment, they are formed to include a plate 131 extending transversely of the chain 121 and a leg 133 which extends rearwardly from the plate 131 and which is suitably connected to the chain 121. Wobble of the plate 131 while traveling along the conveyor bed 113 is eliminated by the provision of a pair of downwardly extending ears 135 (see FIGURE 5) at the outer edges thereof which project in laterally adjacent relation to the outer edges of the upper Ilan-ges of the channel members 111.

Transfer mechanism As previously indicated, the transfer mechanism 65 comprises suitable means designed to individually transfer unclosed cartons from the supply conveyor 61 to a position on the conveyor bed 113 for engagement by one of the pusher elements 123 carried by the main conveyor chain 121. As seen best in FIGURES l, 2 and 3, the transfer mechanism comprises a transfer -arm 151 which includes an L-shaped lever 153 mounted Ipivotally at the end of one of its legs 155 on a pin 157 fastened to the under portion of the stand. At the end of the other leg 159 there isV adjustably connected an upwardly extending post or rod 161, which in' turn, carries at its other end a cantilever 163 supporting a roller 165 for engagement with the carton to be transferred. The projecting length of the cantilever is adjustable by means of a screw 167 in order to vary the throw of the transfer arm relative to the main conveyor so as to enable proper positioning on the conveyor bed of cartons having various widths.V

The transfer arm 151 is rocked' about the pin 157 for travel ofthe roller across theY supply conveyor 61 from a point spaced laterally to the leftof the supply conveyor, as seen in FIGURE 3, to adjacent thefupper run of the main conveyor 63 by engagement with a cam 169 actuated by the drive mechanism 67 in predetermined relation to the travel of the main Conveyor. In this connection, the L-shaped bracket 153 carries a cam follower 171 adjacent the joint of the legs 155 and 159. The cam follower 171 is suitably biased for engagement against the cam 169 by means of a spring 173 which extends from a hook on the post 161 to a connection with the lower portion of the stand. Accordingly, the rotation of the cam 169 and the disposition of the spring 173 and transfer ann 151 operate to effect rocking of the transfer arm back and forth across the supply belt from a position spaced laterally outward of the supply belt to a position adjacent the main conveyor.

In order to prevent operation tof the transfer arm 151 in the absence of a carton positioned properly in the path of travel of the roller 165, the transfer mechanism 65 also includes a control means for restraining the travel of the transfer arm across the supply conveyor. In the disclosed embodiment, this means includes a -pin 175l (see FIGURE l) supported in a bearing 176 and biased by a spring 177 in retractable side abutting engagement with a hub or shoulder 179 formed on the bracket leg 159. Engagement of the pin 175 against the shoulder 179 restrains movement of the transfer arm 151 to the right, as seen in FIGURE 3, across the supply conveyor. Retraction of the pin 175 from engagement with the shoulder 179 is effected by energizing a solenoid 181 (see FIG- URE l) connected in series with a micro switch 183 supported on a stop plate 185 located rearwardly of the transfer arm and disposed transversely across the supply conveyor. The micro switch 183 includes a linger or contact 187 which projects through a central opening in the stop plate 185 and which is disposed so that engagement of a carton against the linger results in the energizing of the solenoid 181. However, the control means is designed so that the retractive force resulting from energizing of the solenoid 181 is less than the friction force existing when the transfer arm biasing spring 173 holds the shoulder 179 in abutting side relation with the pin 175. Thus, the pin 175 will only be retracted by the solenoid, to permit travel of the transfer arm across the supply conveyor, when the cam 169 has outwardly positioned the transfer arm 151 so that the pin 17 5 and shoulder 179 are no longer in engagement.

Front flap folding unit After an uncovered carton is positioned by the transfer mechanism 65 in overlying relation to the flanges of the channel members 111, the travel of the main conveyor chain causes one of the pusher elements 123 to contact the carton trailing side panel 35 for movement of the carton rearwardly along the conveyor path. In this connection, the carton is rst intercepted by the front flap folding unit 69 (FIG. 5) which includes suitable means serving the functions of insuring proper seating of the carton on the conveyor bed and of folding the front cover Hap 45 outwardly of theY carton to provide suicient clearance to permit subsequent infolding of the side cover aps 47 and 49 without interference by the front cover ap 45.

As seen particularly in FIGURES and 6, the front ap folding unit 69 includes an L-shaped bracket 189 which -is lixedly secured along one leg 191 to the main support 109 and a mounting block 192 which defines a portion of the left boundary of the conveyor path and which is secured to the other leg 193 of the bracket 189 in a manner affording vertical adjustment therebetween so as to accommodate cartons of various heights.

In order to assure that thepcarton is properly seated on the conveyor bed 113, a guide ear 194 is carried by the block192 and extends inwardly of the conveyor path in generally parallel relation to the conveyor bed. The forward portion of the ear 194 is curved upwardly so that if the carton is improperly seated on the conveyor bed the upper edge of the front carton flap 45 will be engaged by the ear 194 as the carton moves rearwardly and the carton will be cammed downwardly to effect proper seating on the conveyor Ibed.

Outward folding of the front cover flap 45, relative to the carton, is provided by operation of the oscillating blade 71 which swings downwardly and outwardly of the conveyor path to engage the inner surface of the front cover ap 45 and to thereby effect the desired outfolding. The blade 71 is secured to one end of an oscillating crank shaft 195 which is actuated by the drive mechanism 67 and which is journaled in a supporting plate 197 attached to the mounting block 192 in a fashion permitting vertical adjustment therebetween to enable accommodation of cartons of various depths. l

The oscillation of the blade 71 is correlated, by the drive mechanism 67, with the travel of the main conveyor so that the blade swings downwardly and outwardly of the conveyor path after rearward passage of the leading cover ap 47 to effect outfolding of the front cover Bap 45. As the carton travels rearwardly for entrance under the closure unit 79 to infold the leading cover flap 47, and as the carton travels rearwardly for passage past the trailing flap folding unit 73 to effect infolding of the trailing cover flap 49, the front cover flap 45 is retained in position by means of a downwardly depending lip 194a formed on the rearward portion of the inner longitudinal edge of the ear 194 as seen in FIGURE 6.

Trailing flap folding unit Located rearwardly :of the front ap folding unit 69 to the right of the conveyor path is the trailing flap folding unit 73 which is seen particularly in FIGURES 2, 7, 14 and 15, and which is fabricated to provide means for infolding the trailing cover ap 49 and for maintaining this ap in folded disposition until it travels smoothly under the closure unit 79. In this regard, the trailing flap 49 is folded inwardly of the carton by the camming action of the several spaced apart rotating fingers which are supported on a sub-frame 19S.

The sub-frame 198 includes a right angle bracket 199 (see FIGURES l4 and l5) which is attached along its' horizontal leg 201 to the underside of the main support 109 in a manner, such as a slotted bolt connection, affording lateral adjustment of the trailing at folding unit 73 to permit the accommodation of cartons of various widths. The vertical leg 202 of the bracket 199 depends downwardly and supports an upright member 203 in a manner affording vertical adjustment between the bracket 198 and the member 203 to facilitate the accommodation of different cartons of various depths. The upright member 203 supports at its upper end an arbor 204 which extends transversely of the conveyor path and which carries the camming lingers 75. Each of the lingers 75 is generally L-shaped and is secured at the end of one leg 205 to the arbor 204 in aligned relation with the other fingers. The other leg 206 of each of the fingers extends rearwardly when the fingers are in a downwardly depending position relative to the arbor 204, and is formed along the lower surface thereof to provide a curved camming edge 207 having a radius which extends from the axis of the -arbor 204. The ngers are driven in the clockwise direction, as seen in FIGURE 7, by a sprocket 208 (see FIGURES 14 and l5) which is fixed to the arbor 204 outwardly of the upright member 203 and which is suitably connected to the drive mechanism 67.

As the carton advances along the conveyor path, the action of the rotating fingers 75 is coordinated by the drive mechanism 67 with the travel of the main conveyor. In this regard, the lingers rotate at a speed such that the cammng edge 207 operates to engage the trailing cover ilap 49 in a manner effecting the folding of the trailing cover flap 49 inwardly of the carton and to maintain the trailing ap in this folded condition by bars 265 until the flap is received under the closure unit 79.

Cover tuck folding unit As the carton travels rearwardly of the trailing ap folding unit 73, it enters the cover tuck folding unit 81 which includes means functioning to crease or break-the -fold line 43 between the cover tuck 41 and cover panel 39 and -to dispose the cover tuck inwardly in folded relation to the cover panel. This unit 81, as seen best in FIGURES 8 and 9, is also carried tothe right of the conveyor path by a pair of right angle brackets 211 which are secured along their horizontal legs 212 to the underside of the main support 109 in a manner affording lateral adjustment, such as by a slotted bolt connection, to permit accommodation of cartons of different widths. Secured on the upstanding legs 213 of the brackets 211 is a generally rectangular plate 214 which is adjustably positionable in the vertical direction to yfacilitate employment of the disclosed apparatus with cartons of various dimensions. The plate 214 is carried with its innerface 215 in generally parallel relation to the conveyor path and includes a forward, upwardly extending buttress 216 which has fixed thereon a generally L-shaped member 217. The member 217 is formed to include a leg 218 which is fixed to the buttress 216 and a leg 219 which extends in generally parallel relation to the face 215 of the plate 214 and inwardly of the conveyor path at a distance permitting ease of travel of the cover panel 39 and cover tuck 41 between the leg 219 and the face In order to guide the upstanding carton cover panel and cover tuck for travel between the face 215 and the wardly of the conveyor path. Thus, there is provided a.

pair of curved converging surfaces to guide the travel of the upright cover panel between the leg 219 and the inner face 215.

The cover tuck 41 is folded along the fold line 43 `through the cooperation of a folding element or plow 223 (see FIGURE 9) and a rearwardly extending portion 225 of the leg 219. In this regard, the plow 223 issecured rearwardly on the upper surface of the plate 214 and is fabricated in an irregular shape so as to intercept the travel of the cover tuck 41 and to effect folding of the cover tuck over the upper edge of the rearward portion 225 of the leg 219 and into adjacent relation to the adjoining portions of the cover panel 39. More particularly, the plow 223 is formed with a forward segment 227 (see FIGURE l) adapted to engage the upwardly extending cover tuck and to fold it inwardly of the conveyor path. The segment 227 blends into a rearward generally light angle portion 229 which includes a vertical arm 231 extending in generally parallel and spaced relation to the left of the leg 219 and which functions to effect the folding of the cover tuck along the fold line over the upper edge of the rearward portion of the leg 219. Thus, as the carton emerges from the cover tuck folding unit 81, the cover panel 39 remains in generally upstanding condition between the vertical leg 219 and the plate face 215. In addition, the cover` tuck 41 is folded along the score line 43 and is disposed in generally parallel relation to the cover panel between the arm 231 and the leg 219.

Closure unit Mounted on the left of the conveyor path rearwardly of the front ilap folding unit 69 and in rgenerally opposed relation to the cover tuck folding unit 81 is the closure unit 79. This unit projects into overlying relation to the conveyor path and includes suitably arranged means which function to infold the front and leading cover aps 45 and 47, to close the cover panel 39 over the carton, to insert the cover tuck 41 within the slot 59, and to maintain the various cover flaps in proper disposition Vduring folding of the cover tuck 41, closure of the cover panel 39, and insertion of the cover tuck 41.

As seen particularly in FIGURES 8, 9, 10 and 1l, the unit 79 includes a longitudinally extending beam 251 which forms a rail to the left of the conveyor path for guiding the travel of the carton and which is hingedly carried on the main support V109 to permit the unit to be swung upwardly and outwardly to the left to expose the conveyor path as shown in dotted outline in FIGURE l1. Thus, the entire closure unit may be swung clear of the conveyor path to facilitate cleaning of the `apparatus and unclogging of the equipment in the case of fouling of a carton or cartons. ln this connection, as seen especially in FIGURES l, 8 and l1, the beam 251 is secured to a pair of plates 253 through a slotted bolt connection which affords vertical adjustment of the closure unit 79 to accommodate cartons of different heights. In turn, the plates 253 are joined through a hinge 255 (see FIGURE 1l) with a pair of blocks 257 permanently fixed to the main support 109. The closure unit 79 can be locked in the operating position overlying the conveyor path by a pair of outwardly biased dogs 259 (see FIGURES l, 2 and 8), each of which is secured to a shaft `261 threaded into one of the blocks 257. A handle 263 is also secured to each of the shafts to assist in positioning the dogs 257 in locking engagement with the plates 253.

The closure unit 79 operates to infold the leading cover flap 47 and to maintain the leading and trailing cover aps 47 and 49 in `folded condition during travel of the carton past the unit by means of the bar assembly 77 which includes a plurality of bars 265 supported in parallel spaced apart relation in a generally horizontal plane overlying the conveyor path. More specifically, each of the bars 265 is ixedly secured to a pair of transverse plates 267, which in turn, are attached to a pair of supporting blocks 269 xed to the Ibeam.

Each of the bars 265 is upwardly curved at its forward end as seen particularly in FIGURE 7, to effect infolding of the leading cover ap 47 as the carton is propelled under the bar assembly 77 by action of the mm'n conveyor. In this regard, the forward end of the bar assembly 77 is positioned so that the bars 265 extend forwardly in close relation to the path of the cam fingers 75. This arrangement operates to prevent the carton from kicking forward when the cam fingers engage the trailing cover ap 49, and in addition, smooth passage of the infolded trailing ap 49 is thereby afforded under the bar assembly prior to disengagement by the cam fingers. 4In addition, the bar assembly 77 is also positioned relative to the front ap folding lunit 69 such that the front cover flap 45 is still disposed outwardly of the carton as the leading ap `4'] and trailing ap 49 begin to pass under the bar assembly in folded disposition. Thusly, as the carton is advanced along the conveyor path, the leading flap 47 is infolded by the curved forward ends of the bars 265 and then the trailing cover flap 49 is infolded and subsequently received in infolded condition under the bars 265. Of course, the front cover flap `45 is still in a generally upstanding disposition, as are the cover panel 39 and cover tuck 41 prior to entry within the cover tuck folding unit 81.

As the carton passes through the closure unit rearwardly of the cover tuck folding unit, Vthe front cover flap 45 is folded inwardly of the carton by means of the guide element 84. In this connection, the guide element 84 (see FIGURES 2, 9, 10 and 1l) is supported by the longtiudinal beam 251 and extends inwardly of the conveyor path. As seen in FIGURES 2 and 9, the element 84 is fabricated of sheet metal or other suitable thin material, and is formed with an upwardly curved forward segment 281 which blends into a at rearward segment 283, see FIGURES 2 and 1'1, disposed in parallel relation to the conveyor bed. Thus, the advance of the carton along the conveyor path will cause the front cover flap to be intercepted by the foreward seg- 9 ment 281 which cams the ap inwardly under the at rearward segment 283. In addition, the rearward segment 283 is spaced from the rail-forming side surface of the beam 251 to permit passage of the cover tuck '41 between the rearward segment 283 and the beam 251 for insertion within the slot 59'` as the closing of the cover panel 39 approaches completion.

Folding of the cover panel 39 to close the carton and to permit locking insertion of the cover tuck 41 within the slot 59 is effected by means of the rod assembly 83 which includes a folding rod V271 (see FIGURES 10 and ll) fabricated of rigid but nevertheless flexible material, such as aluminum rod. In this respect, the folding rod 271 is secured to a block 273 mounted rearwardly on the longitudinal beam 251 and is disposed in an inclined fashion across the conveyor path from a point which is spaced rearwardly of the end of the guide element segment 283 and which is spaced from the conveyor bed a distance slightly greater than the depth of the carton to an elevated point rearward of and to the right of the inner face 215 of the cover tuck folding unit. Support of the forward portion of the folding rod 271 is provided by a bridging rod 275 which is fabricated from a material similar to that used in the folding rod 271 and which is welded or otherwise suitably attached to the central region of the folding rod 271. In turn, the bridging rod 275 is secured to an upright post 277 which is connected forwardly of the block 273 to the longitudinal beam 251 in a manner affording vertical adjustment therebetween. Thus, the central region of the folding bar 271 may be adjusted vertically and the exible characteristics of the folding rod 271 permit the forward portion to be suitably positioned to enable successful operation with cartons haJving various dimensions.

As the cover panel 39 cannot be readily folded into a fully closed condition when the bars 265 of the bar assemblyr 77 are located intermediate of the cover panel 39 and the leading and trailing cover aps 47 and 49, and as the disposition of the cover panel 39 `toward the completion of the cover panel folding operation serves to maintain the leading and trailing flaps 47 and 49 in the infolded condition, the bars 265 are terminated at a point forward of the central region of the folding rod 271. With particular reference to the bar 265a which lies adjacent the longitudinal beam 251, this bar is foreshortened with respect to the other bars so as not to obstruct infolding ofV the front cover ap 45 by the guide element 84.

During the terminal portion of the cover panel folding operation, the cover tuck 41 comes into engagement with and is guided for insertion within the slot 59 by the deector 85 which is secured to the longitudinal beam 251 in adjacent relation to the rearward segment 283 of the guide element 84. The deector 85 extends upwardly and slightly to the left from the upper edge of the beam adjacent the conveyor path to provide an inclined surface down which the cover tuck 41 is cammed for passage between the guide element rearward segment 283 and the longitudinal beam 251, to permit entrance within the slot 59 formed by inward folding of the front cover ap 45.

Disposed in generally opposite relation to the rod assembly 83 on the right hand side of the conveyor path there is provided a hold-down assembly 285 (see FIG- URES 2, ll and 19) which isV carried by the laterally adjustable guide assembly 115 and which acts to hold the carton on the conveyor bed and to holdthe portions of the cover panel adjacent the guide assembly 115 in closed overlying relation to the carton. The hold-down assembly 285 comprises a pair of posts 287 and 289 which are connected to the rails 119 in a manner providing for vertical adjustment therebetween. Extending between the posts 287 and 289 in overlying relation to the conveyor path is a rod 291 which is suitably formed to bear against the cover panel 39 andto hold the underlying portions of the cover panel in closed relation to the carton.

Press roll unit .lust after passing rearwardly of the rod assembly 83 and holding'l assembly 285, the carton 25 travels past the press -roll unit 87 Vwhich operates to insure complete closure of the carton and locking of the cover tuck. The press roll unit 87, as seen particularly in FIGURES 2 and 12, is supported to the right of the conveyor path and comprises a generally cylindrical roll 301 which is formed with a ilat 302 (see FIGURES l and 16) and which is rotated so that a point on the outer surface of the roll travels at a speed of approximately one and one half times the rate of travel of the main conveyor. The travel of the at 302 is correlated to the travel of the pusher elements so that the flat 302 is positioned in generally parallel relation to the conveyor bed as the carton begins to travel under the rod. This relation permits smooth entry of the carton under the press roll before the application of pressure and avoids the damage which might otherwise occur as a result of the immediate application of pressure to the leading corner edge of the carton incident to the entry under a completely cylindrical roll. Moreover, the faster rate of travel of the outer surface of the roll as compared to the rate of travel of the main conveyor results in over running of the press roll relative to the cover panel so that a substantially even application of pressure against the top panel is obtained not withstanding the fact that the pressure is not applied immediately upon entry of the leading portion of the carton under the roll.

The roll 301 is carried on an arbor 303 supported by a sub-frame 305. The sub-frame 305 includes generally a right angle bracket 307 which supports an 4upright member 309. The bracket 307 is connected along its horizontal leg 311 to the main support 109 in a manner which provides lateral adjustment of the unit to accommodate cartons of various widths. In turn, the upright member 309 is connected to the vertical leg 313 of the bracket in a fashion permitting elevation of the press roll-301 to accommodate cartons of various depths.

The press roll 301 is driven through a sprocket 315 carried on the arbor 303 outwardly of the upright member 309 and between the member 309 and a support 317 which is xedly attached in spaced relation to thev upright member 309 by means of a spacer 319.

Subsequent to passing under the press roll 301, the carton is discharged from the main conveyor and is positioned on a delivery platform 89 which may take any desired form in order to permit continued travel of the carton to the next packaging operation. In this connection, carton travel off the end of the main conveyor is guided by an irregularly shaped lbail-like rod 321 (see FIGURE 13) which is fabricated of stiif but nevertheless flexible material, such as aluminum rod, which extends in partial overlying relation to the delivery platform, and which is secured to the extreme rear of the longitudinal beam 251 for contacting engagement with the upper surface of the closed carton.

Drive mechanism As has been briefly indicated before, the various moving components of the disclosed apparatus are driven and coordinated by the drive mechanism 67. In this connection, as seen in FIGS. 1 and 3, a suitable electric motor 351V is supported on an under portion of the frame 91 and drives a speed reducer 3'53 through a beltcormection 355. In turn, the speed reducer 353 carries an output sprocket 357 which is connected through an endless chain 359 toa driven sprocket 361 mounted on a main drive shaft 363. The main drive shaft 363 drives the main conveyor 63 through the drive sprocket 124 which is fixed thereon, and, in addition, the main shaft 363 also drives the supply conveyor belt through a linkage including a drive wheel (not shown) which is xed on the main shaft 363 and which is connected by an endless chain 365 to' a The moving elements of the various closure units and the transfer mechanism are driven and coordinated with 'the travel of the main conveyor 63 through a take-off from the main Yconveyor adjacent the rear of the apparatus. In this regard, as seen best in FIGS. 16, 17 and 18, the shaft 373, whichsupports the rear main conveyor idler sprocket 125, also carries a drive sprocket 371 which is connected by an endless chain 375 to a forwardly located driven sprocket 377. The sprocket 377 is carried on a transverse shaft 379 journalled at one end in a depending leg 381 iixed to the main support 109, and journalled at the other end in the press roll unit supporting bracket 307. This shaft 379 also has xed thereon a spur gear 383 in meshing engagement with a driven gear 385 carried on a cross shaft 387 which is also journalled in the depending leg 381 and the bracket 307. Also fixed on the cross shaft 387 are a drive sprocket 389 which powers the press roll 301 and a wheel 391 (see lFIG. 17) through Vwhich the transfer mechanism 65, the front flap folding unit 69, and the trailing ilap folding unit 73 are driven.

'More particularly, the press roll 301 is driven by an endless chain 393 which is trained about the drive sprocket 389 and about the sprocket 315 iixed to the roll supporting arbor 303. In order to take up any slack resulting from vertical adjustment of the press roll, a longitudinally positionable idler sprocket wheel 395 Vis positioned along the rearward run of the driving chain 393. The idler sprocket' wheel 3,95`is supported on a bracket member 397. The member 397, in turn is secured to the vertical leg 313 of the press roll Vunit supporting bracket 307 in a manner affording longitudinal adjustment there-Y 389 and the cross shaft 387 affords selective lateral adjust-ment therealong, such as by means of a set screw, to enable positioning ofthe drive sprocket 389 in vertical alignment with the driven sprocket 315.

The transferl mechanism 65 and the front and trailing ap folding units 69 and 73 are powered through a longitudinally disposed endless chain 401 (see FIGURE l) trained rearwardly about the drive wheel 391 and forwardly, as seen in FIGURE 15, about =a driven wheel 403 carried on a transverse arbor 405 supported by the vertical leg 202 of the trailing Hap unit supporting bracket 199 and by a plate 404 depending from the main support 109. In turn, the -arbor 405 carries a sprocket 407 which is disposed outwardly of the upright member 198 and which drives the trailing ap folding -unit 73 through an arrangement providing'forV lateral and longitudinal adjustments in a manner similar to` that described in regard to the press roll unit This arrangement includes provision, by means such as a set screw, for lateral adjustment of the sprocket 407 relative to the arbor 405 to accommodate lateral positioning of the trailing iiap unit 73, an endless chain 409, the sprocket 208 carried on the arbor 204, and an idler pulley 411 mounted on a member 413 supported on the vertical leg y202 of the bracket 199 in a suitable manner, such as a slotted bolt connection, affording long'- tudinal adjustment therebetween. Driving power for the transfer mechanism 65 and the front ilap unit 69 is supplied through a sprocket 415 which is also'cam'edby the transverse arbor 405 outwardly of the upright member 198 and which drives a cross shaft 416 (see FIGURE 3) by means of an endless chain 414 and a driven sprocketv 418. As the sprocket 415 (see FIGURE 15) is carried on the arbor 405 outwardly of the upright Ymember 198, means, such as 'a set screw, are provided tonpermit relative lateral positioning between the: sprocket.415 and the arbor 405 in accordance with the lateral -positioning of the trailing ap folding unit 73. Of course, similar provisions are incorporated in the connection between the driven sprocket418(see FIG- 12 URE 3) and the cross shaft 416 `to permit alignment of the driving and driven sprockets 415 and 418.

More particularly, as seen best in FIGURES l and 3, the front ilap folding unit 69 is driven by Va cam 415 which isfsupported on the cross shaft 416 and which engages a rotatable cam follower 417 carried at one end of a lever 419. The lever 419 is pivotally mounted ou a pin 421 and is adjustably connected through alost motion connection at its other end to an eyebolt 423 which forms -a part of a connecting link 425. The connecting link 425 comprises a bar 42511 which is threaded at its lower end to the eyebolt 423 and is threaded at its upper end to an eyeblot 427 so that' the effective length of the connecting link 425 may be varied in accordance with the height of the oscillating blade 71. The upper eyebolt 427 is pivotally connected to a crank 431 which, in turn, is fixed to the crank shaft 195. Thus it will be observed that the oscillating movement ofthe blade 71 is provided through a cam driven, crank operated arrangement.

As seen best in FIG. 3, the transfer mechanism 65 is also driven through the cross shaft 416 which carries centrally thereon a helical gear 433. The gear 433 meshes with a driven gear 435 carried on a longitudinally eX- tending shaft 437. Fixed at the forward end of the longitudinal shaft is the cam 169 which engages thecam follower 171 and drives the transfer arrn 151 in the manner previously described.

. Operation The cartons to be closed are deposited on the supply conveyor 61 from a previous packaging operation with the npstanding cover panel 39 disposed generally `in the direction of ktravel of the supply conveyor on the right side thereof. Of course, accurate positioning of the carton on the conveyor is not required as the fence assemblies 107 act to align the cartons for travel along the supply lconveyor toward the transfer mechanism 65.

In this regard, kwhen a carton abutts the stop plate 185 and engages the contact 187, the solenoid 181 is energized to retract the pin 175 from itsV position of side abutting engagement with the shoulder 179 formed on the transfer arm lever leg 159. As previously explained, the transfer arm biasing spring 173 acts to maintain engagement between the shoulder 179 and the pin 175 and, in this connection, the normal force between the pin and the shoulder results in a friction force of larger magnitude than the force generated by energizing the solenoid 181. However, when the drive cam 169 operates to dispose the transfer arm 151 ytoward its extreme outer position, the engagement between the Ypin 175 and the shoulder 179 is broken, and the solenoid 181 effects retraction of the pin 175 to permit travel of the transfer arm across the supply conveyor. When lthus actuated, the roller supported on the transfer arm 151 engages the front panel 29 of the carton Aand transfers the carton from the supply conveyor 61 to the bed 113 of the main conveyor 63 in in a position where the carton will beengaged by one of the pusher elements 123 carried by the endless chain 121.

When the travel of the' endless chain 121 effects engagement ibetween the trailing side panel 35 of the carton and one of the pusher elements 123, the kcarton is propelled rearwardly along the'conveyor path. If the carton is not properly seated on therconveyor bed, it first engages the forward portion of the guide ear,194 supported on the front fllap folding unit 69 (see FIGURE 5) and is cammed into a proper position on theY conveyor bed. -Y Continued rearward movement of theV carton along the conveyor path transports the carton past the oscillating blade 71 of the front ap folding unit 69 '(see FIGURE 6). This blade 71 rocks outwardly to dispose the front cover ap 45 ont- -wardly and in cooperation with the downwardly depending lip' 19411 acts to maintainthe front cover flap in the outwardly directed condition as the rearward movement of the carton continues.` p Y w Immediately subsequent to the outward folding of the front cover ilap 45, the leading cover flap 47 engages the upwardly curved foreward end of the bar assembly 77 and is folded inwardly of the carton. Subsequently, the rotating fingers 75 of the trailing llap folding unit 73 (see FIGURE 7) 'engage the trailing cover flap 49 to effect inward disposition of the ilap and to maintain this ilap in folded disposition for smooth entry under the bar assembly 77. After passage of the leading and trailing cover flaps 47 and 49 past the oscillating blade 71, it swings inwardly and upwardly of the conveyor path in preparation for the next carton.

As the carton continues its travel under the bar assembly 77 with the side cover aps 47 and 49 in inwardly folded disposition, the front cover flap 45, as Well as the cover panel 39 and cover tuck 41 remain in generally upstanding condition. In this regard, the carton then travels past the cover tuck folding unit 81 (see FIGURE 8), and the cover panel 39 and cover tuck 41 are guided by the converging surfaces of the guide 220 and ear 221 for travel between the inner face 215 of the plate 214 and the leg 219 of the L-shaped member 217. Toward the rear of the cover tuck folding unit 81, the cover tuck engages the plow 223 (see FIGURE 9) and is foldably disposed over the upper edge of the rearward portion 225 of the leg 219 into a generally parallel relation to'the cover panel 39 between the arm 231 and the `leg 219. Thus, when the carton emerges from the cover tuck folding unit 81, the cover panel 39 is still in generally upstanding position. However, the resiliency of the paperboard from which the carton is fabricated causes some reverse folding of the cover tuck 41, and thus, when the cover tuck folding unit is cleared, the cover tuck 41 is folded at about a right angle in relation to the cover panel.

As the carton continues to move rearwardly along the conveyor path, the front cover ilap 45 engages the guide element 84 and is foldably disposed inwardly yof the carton. During this operation, the leading edge of the cover panel 39 is intercepted by the forward portion of the folding rod 271. As the rearward movement of the carton progresses, the cover panel 39 is cammed downwardly by action of the folding rod 271 into covering relation to the carton. As this operation approaches completion, the leading and trailing cover aps 47 and 49 pass rearwardly of the ends of the bars 265 and are held in infolded condition by the partially closed condition of the cover panel 39. In addition, the front cover flap 45 travels rearwardly in inwardly folded condition under the guide element segment 283 during the terminal portion of the cover panel closing operation.

Near the completion of the cover panel folding operation, the cover tuck 41 contacts the deflector 85 and is cammed downwardly so that it passes between the longitudinal beam 251 and the rearward portion 2-83 of the guide element 84, and enters the slot 59 for locking engagement therewith. Simultaneously with the termination ofthe cover panel closing and the cover tuck inserting operations, the carton passes under the holding assembly 285 disposed on the right side of the conveyor path.

When the closed carton emerges rearwardly from the holding assembly 285 and the rod assembly 83, it travels past the press roll unit 87 and under the press roll 301. In this connection, the press roll is suitably spaced from the conveyor bed to effect full closure of the cover panel 39 and to complete the locking engagement of the cover tuck 41 with the front cover ap 45. Rearwardly of the press roll unit 87, the carton travels under the bail-like rod 321 and is deposited on the delivery platform 89 for transportation to the next subsequent packaging operation.

Of course, it should be readily understood that the device of the present invention is not limited for use with the particular carton disclosed. The adjustable attach- Clt ment of the various units and the guide rails about the supply and main conveyors permit utilization of the disclosed apparatus with cartons of various lengths, widths, depths, cover ilap and cover tuck formations.

Various changes and modifications may be made in the disclosed construction to achieve various of the features mentioned herein without 4departing from the principles of the present invention. Various features of the invention are set forth in the appended claims.

I claim:

1. A machine for closing cartons having a cover flap extending from one side wall, a cover panel extending from an opposed side wall, and a cover tuck projecting from the cover panel, said machine comprising a main conveyor, a supply conveyor, and a transfer mechanism for transferring individual cartons from said supply conveyor to the main conveyor at predetermined intervals, said main conveyor having located therealong means for folding the cover flap -inwardly of the carton, means for folding the cover tuck inwardly of the carton relative to the cover panel, and a means for folding the cover panel into overlying relation to the carton while maintaining the cover flap in folded condition and for inserting the cover tuck within the carton while folding the cover panel and maintaining the cover flap in folded condition.

2. A machine for closing generally rectangular cartons having front, rear, and opposed side walls, a cover flap extending from each of the front and side walls, a cover v panel extending from the rear wall, and a cover tuck projecting from the cover panel for locking engagement with other portions of the carton to maintain the carton in closed condition, said machine comprising a main-conveyor, a supply conveyor, and a transfer mechanism for transferring individual cartons from said supply conveyor to said main conveyor at predetermined intervals, said main conveyor having located therealong means for folding the front cover flap outwardly of the carton, means for folding the side cover flaps inwardly of the carton, means for folding the cover tuck inwardly of the carton relative to the cover panel while maintaining the folded disposition of the side cover aps, means for folding the front cover flap inwardly of the carton while maintaining the folded condition of the side cover aps, means for folding the cover panel inwardly of the carton while maintaining the cover aps in folded disposition, means for inserting the cover tuck within the carton while folding the cover panel and maintaining the cover flaps in folded condition, and means for applying pressure to the cover panel to insure complete closure and to effect locking of the cover tuck.

3. A machine for closing generally rectangular cartons having front, rear, and opposed side walls, a cover flap extending from each of the front and side walls, a cover panel extending from the rear wall, and a cover tuck projecting from the cover panel for locking engagement with other portions of the carton to maintain the carton in closed condition, said machine comprising a main conveyor, a supply conveyor, and a transfer mechanism for transferring individud cartons from said supply conveyor to said main conveyor at predetermined intervals, said main conveyor having located therealong means including an oscillating blade for folding the front cover flap outwardly of the carton, means including a rotating element for folding one of the side cover flaps inwardly of the carton, means for folding the other of the side cover aps inwardly of the carton, means for folding the cover tuck inwardly of the carton relative to the cover panel while maintaining the folded condition of the side cover aps, means for folding the front cover flap inwardly of the carton while maintaining the folded disposition of the side cover aps, means for folding the cover panel inwardly of the carton while maintaining the cover aps in folded disposition, means for inserting the cover tuck within the carton while folding the cover panel and maintaining the cover aps in folded condition, means including a rotating cylinder having a at segment for applying pressure to the cover panel to insure `complete closure and to effect locking of the cover tuck, and means for driving said main conveyor, said'transfer mechanism, said oscillating blade, said rotating element, and said rotating cylinder in predetermined relationship.

4. A machine for closing generally rectangular cartons of various dimensions having front, rear, and opposed side walls, a cover flap extending foldably from each of the' front and side walls, a cover panel extending foldably from the rear Wall, and a cover tuck projecting 'om the cover panel for locking engagement with other portions of the carton to maintain the carton in closed condition, said machine comprising a stand including a supporting member, a main conveyor iixedly secured to said supporting member and including an endless chain having a plurality of sequentially spaced pusher elements located along said chain, and a guide means located along one side of said conveyor and secured to said supporting member in a manner affording selective lateral positioning relative to said main conveyor, a supply conveyor carried on said stand, a transfer mechanism supported on said stand for transferring individual cartons from said supply conveyor to lsaid main conveyor at predetermined intervals correlated to the spacing and travel of said main conveyor pusher elements, a rst means including an oscillating blade for folding the front cover flap outwardly of the carton, said rst means being located along the other side of said main conveyor and being secured to said supporting member in a manner affording selective vertical positioning relative to said main conveyor, a second means including a rotating element for folding one of the side cover aps inwardly of the carton while the outfolded disposition of the front cover nap is maintained, said second means being located along the one side of said main conveyor and being secured to said supporting member in a manner affording selective lateral and vertical positioning relative to said main conveyor, a third means for folding the other of the side cover aps inwardly of the carton and for receiving the one side cover fla-p in folded disposition, a fourth means for folding the cover tuck inwardly of t-he carton relative to the cover panel while the inwardlyY folded disposition of the side cover iiaps is maintained, said fourth means being located along the one side of said main conveyor and being secured to said supporting member in a manner atfording selective lateral and vertical positioning relative to said conveyor, a iifth means for folding the front flap inwardly of the carton while maintaining the side coverraps in inwardly folded condition, a sixth means for folding the cover panel inwardly of the carton while maintaining the cover Vflaps in inwardly folded condition, a seventh means for inserting the cover tuck within the carton while folding the cover panel and maintaining the inwardly folded condition of the cover flaps, said third and fifth through seventh means forming a unitary structure in generally overlying relation to said main conveyor and being supported along the other side of said main conveyor in a manner providing a guide for the travel of the cartons being closed and being hingedly connected to said supporting member to enable access to the Vconveyor path, said hinged connection being provided in a manner affording selective vertical positioning of said unitarystructure relativetto said conveyor, means including a rotating cylinder having al flat segment for applying pressure tothe cover panel to insure complete closure and to effect locking of the cover tuck in a manner providing for entry Vof the carton under the ycylinder before application of pressure, said last mentioned means 'being located alongthe one side of said main conveyor and being secured to said supporting member in a manner affording selective lateral and vertical positioning relative to said conveyonand a means for driving said main conveyor, said transfer mechanism, said oscillating blade, said rotating element, and said rotating cylinderin predetermined relationship. Y 5.l In a machine for closing cartons of various dimensions formed with a cover panel and a cover tuck extending from the cover panel for locking engagement with other portions of the carton, the combination cornprising a `supporting member, a conveyor mounted on said member and carrying cartons to be closed at predetermined spaced intervals therealong, means for driving said conveyor along a predetermined path, a frame secured to said member, an arbor journalled in said frame and extending transversely of said conveyor path, a roll carried by said arbor for engagement against the cover panel to complete closure of the cover panel and to eifect locking engagement of the cover tuck with the other portions `of thev carton incident to complete closure of the cover panel, said roll including a at, means alording selectivepositioning of said frame in the vertical and lateral directions relative toV said conveyor path to accommodate cartons of various dimensions, and means for rotatably driving said rollin predetermined relation to the travel of 'said conveyor 'and to the spacing of the cartons therealong lso that said flat is positioned in generally parallel relation to the conveyor path as the carton enters under the roll, said roll driving means including a driving wheel can-led by said supporting member, a driven wheel carried on said arbor, an endless member trained about said Wheels, and an idler wheel carried kon said frame in a manner affording selective positioning relative to one run of said endless member to remove slack in said endless member occurring incident to vertical positioning of said frame.

References Cited in the le of this patent UNITED STATES PATENTSy 816,124r Reynolds Mar. 27, 1906 1,956,531 Jones' Apr. 24, 1934 2,598,135V Schmied May 27, 1952A 42,625,778 Wood Jan. 20, 1953 2,660,012 Boyce et al Nov. 24, 19'53 2,665,532 Wood Jan. 12,1954 2,713,410 Irmscher July 19, 1955 V2,762,487 Temple Sept. l1, 1956 

